use GlobalId in eval_to_valtree query and introduce query for valtree_to_const_val

compiler/rustc_middle/src/mir/query.rs

@@ -1,6 +1,6 @@
 //! Values computed by queries that use MIR.
 
-use crate::mir::{Body, Promoted};
+use crate::mir::{self, Body, Promoted};
 use crate::ty::{self, OpaqueHiddenType, Ty, TyCtxt};
 use rustc_data_structures::stable_map::FxHashMap;
 use rustc_data_structures::vec_map::VecMap;
@@ -413,13 +413,20 @@ pub enum ClosureOutlivesSubject<'tcx> {
     Region(ty::RegionVid),
 }
 
-/// The constituent parts of an ADT or array.
+/// The constituent parts of a type level constant of kind ADT or array.
 #[derive(Copy, Clone, Debug, HashStable)]
 pub struct DestructuredConst<'tcx> {
     pub variant: Option<VariantIdx>,
     pub fields: &'tcx [ty::Const<'tcx>],
 }
 
+/// The constituent parts of a mir constant of kind ADT or array.
+#[derive(Copy, Clone, Debug, HashStable)]
+pub struct DestructuredMirConstant<'tcx> {
+    pub variant: Option<VariantIdx>,
+    pub fields: &'tcx [mir::ConstantKind<'tcx>],
+}
+
 /// Coverage information summarized from a MIR if instrumented for source code coverage (see
 /// compiler option `-Cinstrument-coverage`). This information is generated by the
 /// `InstrumentCoverage` MIR pass and can be retrieved via the `coverageinfo` query.